In the manufacture of metal strips having transversely extending corrugations along the length thereof, it is common to feed the stock from a coil between forming rolls to form the corrugations. Typical apparatus for use in such manufacture is shown, for example, in U.S. Pat. Nos. 3,998,600, 4,067,219, 4,262,568 and 4,507,948. Ribbon stock is typically withdrawn from the coil by pinch rollers or the like. Coil inertia and drag during start-up deleteriously affect control of fin height. Moreover, such inertia and drag vary as coil diameter decreases. In the event of machine shut-down, coil momentum continues to unwind ribbon stock. When the supply of ribbon stock from a coil is exhausted, it becomes necessary to stop the machine, remove the spool of exhausted coil, replace it with a fresh coil and restart the machine.
Among the objectives of the present invention are to provide an uncoiler apparatus to be utilized with a corrugated fin rolling machine which will facilitate the rapid change of coils; wherein the coil is positively driven in timed relation to the machine to reduce problems associated with varying drag and inertia at the coil; wherein the control of the drive is varied as the radius of the stock on the coil is reduced; and wherein the speed of drive is controlled to provide a proper and continuous speed of formation of the corrugated metal strip.
In accordance with the invention, in an apparatus for rolling metal ribbon stock into convoluted fin strip for use in heat exchangers, an uncoiler apparatus comprises a base and a pair of coil supports for supporting a pair of coils of sheet metal ribbon stock. The coil supports are mounted on a plate which is rotatable about a vertical axis so that when the plate is rotated, one coil support is moved into driving engagement with a coil device motor and the other coil support is moved out of driving engagement with the motor. A control system interconnects the drive of the motor on the uncoiler apparatus with the drive of the remainder of the corrugated fin rolling machine.